Dealer Stumped

[AlaTex]

Issue seems to have dealer stumped also - -

 

2005 GMC Yukon 2WD

approx 21,500 miles (still under warranty)

 

1. Upon leaving on long trip after about 20 miles of 800 mile trip (oneway), a warning light (red) flashed briefly on instrument panel and went off before I could determine what it indicated. There was no apparent change in drive ability. Light did not come on again since 2000 miles plus on trip.

 

2. Standard service at dealer after returning from long trip 1 week ago.

 

3. Only drove approx. 40 miles after service. Did not drive this vehicle for 3 days.

 

4. On Weekend, the back doors and tailgate would not unlock with key fob or door switch on drivers side door.

 

5. Today I was going to take it in to dealer. When I went to unlock front door, it would not unlock with key fob. After using key to unlock door, vehicle would not start - motor turned over OK (no apparent weakness from battery), none of the doors or lift-gate would unlock with key fob or door switch and power windows would not work.

 

6. After trying 20 -30 times to start Yukon , I call dealer. Then called AAA for tow, but before tow truck arrive 1.5 hr. later, I tried to start again. It started OK. Called and canceled tow truck. Left immediately for dealer 1.5 miles away. Halfway there, at a major intersection stop light, the Yukon died. Initially it would not start. Put hazard light on, reached for phone to call for tow truck while continuing to attempt to start. After about 5 attempts it again started with no problem and seemed to be having no problems i.e. engine running OK. Drove on to dealer and left it. Described all issues I was aware of and demonstrated to dealer unlock problems. I left motor running at dealer. Also noticed at dealer that clock had apparently reset its self reading 12:15 even though it was actually approx. 9:20. Dealer called late today and said they were stumped and need to keep.

 

Need suggestions Please.

[asilverblazer]

Bad ground screwing with the security system. Causing it to die at an intersection?

[jlcallaway]

It sounds like a total electrical failure to me since your clock lost time. It has to be at a point that could effect the total vehcile.

 

Otherwise on my 2500 HD it sounded like the same failure I had when it would start when it wanted and stopped whenever. It turned out to be the crankshaft sender that had partially failed. Replaced it and have no reoccurance since. HOwever, I did not have other electrical problems at the same time.

 

JoJoJim

[BigJayDogg3]

Might be a short in the batt cables? Or maybe somewhere past the alt?

[lord-dogbert]

Power distribution, perhaps the little red box where the positive leads all come together under the hood or bad ground.

[bobcat5544]

With all the problems you have listed there is one common source that can cause all of this. There is a ground wire on the left upper part of the dash also known as G203. I have seen that connection come loose and cause similar problems to yours.